Hello there, long time lurker first time poster. I recently installed the transformer hd2 kit on my 4l80e. I used the transgo separator plate. I now have my transmission apart because the direct piston broke. Wondering if besides actually doing the internal feed I would just need the original separator plate or will the hd2 plate be ok? I know the hd2 plate “dual feeds” per say but if I leave out the seals on the direct is it ok to run like that?

Basically do I need to undo the hd2 kit to dual feed properly?

thank you

 

If you are removing the pump from the transmission, there is no reason to use the HD2 kit. It is meant for a transmission that is in good condition so that you do not have to take it apart to dual feed it.
Undo all the HD2 mods and dual feed the direct clutches the right way internally.

 

The dual; feed (hate that word as it misleading , it's actually only one feed but using both parts of the piston) but the TG and removing the seal have same result and work with each other to so no reason to change anything if you were happy with trans as it worked prior,
I am concerned with breaking the direct piston? Is this early style with aluminum piston ? if so just replace with late moulded style and sprig cage and no worries again. But still odd breaking it .

 

Yeah, if you are dual feeding by leaving the seal out and plugging the the feed hole on the case, absolutely no reason to use the Transgo HD-2 separator plate. There's reports of those HD-2 separator plates causing issues due to cross leaking fluid, so you eliminate that possibly.

 

ditch the HD2 plate and use your original plate.. hopefully you did not do the pressure relief mod in the valve body, if not it can be undone with a set screw. I wouldn't use anything from the transgo kit except maybe the boost valve assembly. everything else is for the "wow" factor, all the springs they have you add in the VB, etc

 

The Early 4L80E Clutch Pistons were Aluminum and do actually fracture more commonly than any other THM400 Aluminum Clutch Piston.

These Pistons look like the Image below:



-Marcello III

 

And Yes the Commonly stated: "Dual-Feed" is a misnomer.
As Frank said it is actually a Single-Feed with Both Direct Piston Chambers Applied.

Many of the Billet THM400 Valve-Bodies are actually a Dual-Feed with Both Direct Piston Chambers Applied.

-Marcello III

 

This is the one I had that broke. It separated at the ridges, basically left the bottom “disc” and top “hat”

I’ll use my old separator plate, thanks for the replies


I will throw in the bonded pistons as well. Any preference on brand?

 

I need someone to verify this; however I believe the Early (1996 and Down) Forward Drums do not properly fit the Bonded Apply-Pistons.

I believe the Early (1996 and Down) Forward Drums share the THM400 Dimensions, and would use an Aluminum Apply-Piston from the THM400.

-Marcello III

 

I did read somewhere they worked as well as seeing a kit from ck performance to convert to the bonded pistons. I hope they do since I already ordered mine.

 

Think they do work but you have to use the one for the direct in the forward as they have two different center sizes